Fuel pump



Patented Sept. 13, 1932 UNITED STATES` PATENT oFFlcE FRITZ GOSSLAU, F BERLIN-CHARLOTTENBURG, GERMANY, ASSIGNOR T0 SIEMENS & HALSKE, AKTIENGESELLSCHAFT 0F SIEMENSSTADT, NEAR BERLIN, GERMANY, A.

CORPORATION or GERMANY FUEL PUMP .Application 1ed'September'22, 1930, Serial No'.v483,5/56, and in Germany October 1, 1929.

My invention relates to internal combus tion engines, and more` p articularly to the feed pumps forthe liquid fuel of such enf, gmes. ,y

The object of my invention is to provide an improved valveless fuel pump of the type in which the quantity of fuel lis regulated by rotatably adjusting the piston of the pump. lp

An embodiment vof my invention -is illustrated in the drawing aliixed to my specification and forming a part thereof. Inl this drawing:

Fig. 1 represents a fuel pump for the airless injection of fuel in to a Diesel engine, in longitudinal section, and

Fig. 2 a crosse-section of a detail of said pump along line A-B of Fig. 1.

Referring to the drawing it will be seen that the pump has no intake valve. The fuel is supplied into pump chamber 4 from the supply duct 1 throughthe port 2, so long as this port is uncovered by piston 3. The fuel is delivered upwardly, as soon as the'piston 3 on its upward stroke covers the port 2 andsep.- arates the pressure chamber 4 from supply duct 1. When the required delivery pressure has been attained in the compressionv chamber, the spring-controlled valve 5 opens and the fuel is delivered'to the engine cylinder by a pipe not shown in the drawing.-

Movement is imparted to the piston 3 by a cam 7, keyedto the shaft 6, through a tap-v -pet oi' plunger 8 provided with an anti-friction roller. The quantity of fuel to be delivered may be regulated by rotatably adj usting the piston 3. For this purpose the head of the piston is not flat, but spirally curved so that the time during which the piston 3 covers the inlet opening 2 varies according to the adjusted angular position of the piston. The piston 3 can be rotatably adjusted by means of a rack 9 engaging` the pinion 10 mounted on the regulating sleeve 11. The sleeve is at its 4lower end provided with two slots 12 in which are located the two ends of a transverse bar 13, fixedin the Y 'piston rod. In the hitherto disclosed designs of such pumps the movable parts of the pump are arranged to be withdrawn from the bot-vv piston barrel tom of thepump casing after the cam shaft has been removed.

For many purposes it is, however, undesirable to remove the pump from below, for instance in internal combustion engines with radially arranged cylinders in which the fuel ppmps are likewise located radially in a single ane. f

The object of my invention is to provide a fuel pump of this type whose' operating parts may easily be removed through the top of the casing. I attain this by connecting the pump piston 3 with the tappet or plunger 8 by means of'a bayonet joint.

Referring more particularly to Fig. 2 of the drawing it will be observed that the foot 15 of the piston 3 is ofoblong shape correspondin g with the shape of a slot 14 in the top of tappet 8. By turning thepistonits foot 15 can beset to register with the opening 14 and be passed through it into a low chamber in the tappet, whereupon it may be locked by setting itat an angle, preferably of 90, to the slot. The uncoupling of the two parts is effected in the reverse way in a very simple manner.

According to my invention v'the lower part of the regulating sleeve 11 in which the slots 12 are provided is contracted suiiiciently to permit the location of the two ends of the transverse bar'13 of the piston rod 3 within the inner diameter of the remaining portion of the sleeve, so that the bar can pass through sleeve 11 when the piston and the barrel are withdrawn upwardly.

If a breakdown occurs in a fuel pump of this construction the pump may easily be withdrawn toward the top, for the purpose of repairs. To effect this the valve box in which the delivery valve 5 is housed is first removed. The pump piston Sis then turned until its foot registers with the slot 14 in the tappet. B unscrewing the screw 16 which locks the barrel 17 in' the housing, the piston 3 together with the barrel 17 may then be lifted out through the top of the casing.

I claim as my invention:

A fuel pump having a casing, a stationary and a'reciprocating piston disposed therein, and having means for varying the amount of fuel delivered by varying. its

y:ses

angular posizltlininthe barret a regu-tin sleeve rotata l adjustable in the casing an containing sai rbarrel and piston, said sleeve being `contracted at its lower end to substantially the diameter of said barrel2 and having diametrically opposite'longitudmal slots in the contracted portion and-a transverse bar fixed in said lpiston and engaging said slots with its free ends, for couplin said piston fosaid barrel and piston throughl the upper end of said sleeve and the outerend of said casing. f Y

In testimony whereof I ax my siature.

v FRITZ GOS AU. 

